Number of acute triangles, distinct up to congruence, on an n X n grid (or geoboard).

Terms

a(0) =0a(1) =0a(2) =2a(3) =8a(4) =23a(5) =51a(6) =101a(7) =179a(8) =295a(9) =460a(10) =688a(11) =988a(12) =1382a(13) =1876a(14) =2495a(15) =3258a(16) =4191a(17) =5298a(18) =6613a(19) =8166a(20) =9973a(21) =12065a(22) =14472a(23) =17208a(24) =20341a(25) =23873a(26) =27838a(27) =32282a(28) =37238a(29) =42734